NOPR Collection:

Reaction of N(²D) with O₂: Not a major source of O(¹D) atoms in aurorae

Fri, 01 Feb 1991 00:00:00 GMT

Title: Reaction of N(²D) with O₂: Not a major source of O(¹D) atoms in aurorae Authors: Singh, Vir Abstract: The reaction of N(²D) with O₂as a source of O(¹D) proposed by Rusch et al. [Geophys Res Lett (USA), 5 (1978) 1043] is restudied in the light of recent measured reaction rate coefficients. The present results indicate that this reaction is not a major source of O(¹D) atoms in aurorae. Page(s): 76-77

Photo-ionization balance and ion composition model on the ionospheres of Mars and Venus

Fri, 01 Feb 1991 00:00:00 GMT

Title: Photo-ionization balance and ion composition model on the ionospheres of Mars and Venus Authors: Swamy, A C Balachandra Abstract: Photo-ionization rates on the ionospheres of Mars and Venus have been computed using the latest available data such as Hinteregger solar fluxes, photo-ionization and photo-absorption cross-sections and the neutral atmospheric models. Photochemical equilibrium has been assumed in the height range 100-300 km. The derived N_e(h) profiles are compared with the observed N_e(h) profiles. There is thermal equilibrium (T_e = T_g) in the case of Martian ionosphere. However, there is thermal imbalance (T_e>T_g) on the Venusian ionosphere above 160 km. Ion density profiles have been derived by the application of appropriate photochemistry. There is an excellent agreement between the observed and computed ion density profiles below 200 km in both the ionospheres. Page(s): 68-75

Field line tracing in a realistic magnetosphere

Fri, 01 Feb 1991 00:00:00 GMT

Title: Field line tracing in a realistic magnetosphere Authors: Mukherjee, G K Abstract: Field line tracing has been carried out using realistic magnetic field models for different ranges of magnetic activity. It is shown that the non-dipolar radial and azimuthal distortions in the field line geometry are extremely model dependent and choice of the magnetospheric magnetic field model may be critical in understanding several magnetospheric phenomena. Page(s): 65-67

IEC and equivalent slab-thickness at Taiwan

Fri, 01 Feb 1991 00:00:00 GMT

Title: IEC and equivalent slab-thickness at Taiwan Authors: Vijay, S K; Singh, Manjesh; Gwal, A K Abstract: The diurnal and seasonal variations of IEC_max and IEC_min, noontime biteout, nighttime enhancement in ionospheric electron content (IEC), and equivalent slab-thickness over Taiwan (24.9°N, 121.3°E) have been studied for the quiet days. In general, in the diurnal and seasonal variations of IEC, it is observed that IEC attains minimum value around 0400-0500 hrs LT except in winter months, and the rate of decrease of IEC after reaching maximum is more steep during pre-midnight hours than that during post-midnight hours. The effect of noontime biteout is found more pronounced during summer rather than winter or equinoctial months of 1983-84. Moreover, the nighttime enhancement phenomenon shows the same trend. The seasonal variation of the equivalent slab-thickness of the ionosphere at Taiwan has also been studied and the occurrence of the secondary enhancement has also been observed and discussed. Page(s): 61-64

NOPR Collection:

Reaction of N(2D) with O2: Not a major source of O(1D) atoms in aurorae

Photo-ionization balance and ion composition model on the ionospheres of Mars and Venus

Field line tracing in a realistic magnetosphere

IEC and equivalent slab-thickness at Taiwan

Reaction of N(²D) with O₂: Not a major source of O(¹D) atoms in aurorae